Power-dipper door-latch release



April 29, 1930. L. R. CULVER 6, 8

POWER DIPPER DOOR LATCH RELEASE Filed Jan. .25, 1929 3 sheets-sheet 1 ii-foxy April 29; 1936. L. R CULVER 1,756,284

' POWER DIPPER noon LATCH RELEASE Filed Jan. 23, 1929 3 Sheets-Sheet 2 jI EA TOR,

Caz V56 4 TOR/VII.

ent re Tl rar s men It. enliven, or? ps cALiroaiirA, remade is etreat Tor-iii W. rainrnivrann'nn ELLA .rjrarmaiaar or VISTA; cannon-me PoyvER-DIPPER mammal-r RELEAS Application fi1eZ1' J'anuary 23, 929; Serial' No. 334,519.

My invention relates; generally to power shovels, particularly those of the gas-air type, and mo-re'specifically'to means for'releasing the'latch that normally holds the door of the dipper in closed position, and my present invention is an improvement upon the power dipper door latch trip set forth in mycopending application rates; Letters Patent filed August 11, 1928, Sr. No. 299,058; v

The principal objects of my present invention are to generally improve upon and simplify theconstruction of thev dipper, door latch releasing means disclosed in my aforesaid patent-application, to provide a latch tripping device that. is capable of being applied to practically all makes of shov els Without altering the construction thereof or involving special machine Work on the partsthereof, and, further, to provide a latch releasing device that is relatively simple in constructiom inexpensive f-mam utacture, capable of being easilyandquickly "applied to the shovel for use,'andvvhichiis tive and efiicient in operation;

strong andidurable in construction and posi- It Willbe understood that the dipper door latches of power shovels aregenerally actuatedby means of a cable, a portion'otwhich winds upon a 'drum andit isoneof the ob-f ectsoffmy invention to provide simple and eliicient means that Will at all times and under all conditions take up the slack in the latch releasingcable and yet permit the dipper to be manipulated While being filled ithout drawing the cable sufic'iently taut to release the dipper door latch'a-nd further'to provide simple and efiicient means vunder control of a foot pedal for actuating thelatch'j releasing 1ll6l11S,'tU1Cl further to provide a brake that cooperates Withithe cable carrying drum for preventing the latch actuating cable'from unwinding When'the'povver shovel is reversed or moved rearWardly.

With the foregoing and other objects view, my. invention consists in certainnovel features of construction and arrangement of parts that-Will hereinafterbe more fullyde scribed and claimed and illustrated in the accompanyingdrawings, in which 1 Fig. 1 is a side elevational view of a gas-air Fig. 3 is an elevationall vievv ,oft-he ilever door latch releasing means applied v ona lri w qfmy mproved d pper door; latch releasing means Wlll ll parts bro-ken away-and in section.

that is t iz pr app yi pres j revt the frictipn disks that cooperate With the cable carrying drum,

mat'ely on the line l-ofFigfl v i K pedal; that is utilized for actuatingthe latch releasing; means; i

a Fig. 6' is a side elevational-Vievv the pedal. a

Referring by numerals to the accompany; 111g drawings which llustrate a-PlfalctlCaLBHlbodiment of myinvention, v 10 designates; a

cab. ofga gas-air1shovel vvhich cab is generally mounted on a caterpillar tractionba se 11, said cab enclosing theiengine' and'thegreater' portionof theoperatingparts of the,,-shovel including themain drum gear wheel 12.; I

a a a to Fig. :4: is a Vertical section taken approxi V Projecting from thei frontof the cifb a;

boom 13 upon: which" is arrangech for opera? tion' inthe-usual-manner,- tlieidipp'erqstick-I 14:? carrying at its lower end the dip'perg'or shovel l5, and the'latteri being provi'ded with the-usual drop door :16 that is'normally retained in closed position by a latch-:17.

Secured to thelatch 1 is one end of a cable 18 that extends. into the cab 10 to. my: im-

proved latch, releasing means. and which cae ble is conveniently supported I v on the boom 13 by a pulley suchaslt). 1

Arranged iiiithe front; portion ofthe cab a is the operators'seat'20yin frontofiwvhich is positioned the usual: operating: or control levers2l and arranged on'the floor of. the cab V is the usnal'main control Vanessa; T -i Lea-dingirom this main valve to the trans:

missionrami's a fiuid pressure pip'e23 and leading from saidi-valveto the reverse ram is a fluid pressure pipe 24;

latch releasing means contemplated by my invention is convenientlysupported upon a suitable bracket :25 thatis detachably se= cured in any suitable manner, preferably by iro' means of J-bolts 26, to a transverse beam that forms a part of the gantry frame of the machine and said bracket being positioned just 7 above the main drum gear wheel 12.

keys or feathers on said projecting end are the hub portions of a pair of disks 31.

These disks aremounted so that they slide toward and away from each other upon their keys or feathers, and they are retained on the shaft by a nut 32 that is'secured on the end of the shaft and by a thrust bearing 33 that is mounted on the shaft just beyond the inner one of the pair of disks. I

Arranged to rotate freely upon the hubs of the disks 31;and between the same is a drum or pulley 34 upon which is wound a considerable portion of the cable 18 and the inner end of said cable being secured to the periphery of said drum, as illustrated in Fig. 2.

Carried by-the inner faces of the outer portions of the disks 31 are clutch facings 35 that are adapted to engage the outer faces of V the drum or pulley 34.

Formed-in the end of shaft 28 on which the disks and cable receiving drum are mounted is an axle bore 36 on the outer end of which is seated a grease cup 37 and leading from the inner end of said bore outwardly through the shaft 28 are axially disposed ducts 38 that carry the grease or lubricant from the chamber 36 tothe periphery'of the shaft upon which the hubs of the disks 31 are mounted.

Formed through the disks 31 just inside those portions that carry the clutch facings 35 are lubricant-discharge ducts or openings 39 having inclined bottoms, and these openings are arranged so that lubricant passing outwardly from the hub portions of the disks will discharge to the outer faces of the outer portions of said disks instead of passing outwardly between said disks andthe drum 34,

in which latter event the clutch facings would become impregnated with lubricant and they would'soon lose their efficiency.-

Depending from the bearing 27 is an arm 40 and secured thereto is a bracket 41. Formed in s aidarm and bracket are coinciding apertures in which is seated a bushing42 and passing through the latter is a push rod 43, the inner end thereof being arranged for sliding movement in the inner portion of the bracket Mounted on a threaded portion of rod 43 is a nut 44,-and interposed between said nut and the inner portion of bracket 41 is an expansive coil spring 45. The outer end of rod43 passes through the lower portion of a Y- shaped lever 46, the latter being fulcrumed on a pin or bolt 47 that passes through ears 48 that project from the outer face of bracket 25 just above the bearing 27 Formed on the outer face of the lever 46 to the sides of shaft 28 are lugs 49 that bear against the thrust bearing 33.

'Mounted on the outer portion of push rod 43 is a nut 50 that bears against the rear face of the lower portion of lever 46.

Fulcrumed on the inner lower portion of bracket 41 is a bell crank 51 and the upturned short arm thereof bears against the inner end of push rod 43.

Mounted on the floor of the cab directly in front of the operators seat 20, and preferably directly above the shaft on which the control levers 21 are mounted, is a block 52 on which is fulcrumed a pedal 53 and fulcrumed on the block below the front portion of this pedal is a bell crank 54, one arm of which is connected by a link 55 to the foot pedal 53 in front of its fulcrum.

Clamped in any suitable manner to the opposite arm of the bell crank 54 is one end of a flexible member 56, preferably a section of piano wire, and the opposite end of this flexible member is clamped in any suitable manner to the long arm of thebell crank 51. This flexible member is enclosed in a flexible metal sheath or cable 56, one end of which is clamped to block 52 and the other end being secured to the lower portion of bracket 41.

Projecting outwardly from the lowerportion of arm 40 is a rod 57 and carried thereby is spool 58 that is positioned directly beneath the drum 34 and said spool serving as a guide for the cable as it winds on to and from said drum.

Projecting outwardly from the upper portion of bracket 25 is an arm 59 that terminates above the drum 34 and secured to said. arm directly over the drum is a cylinder 60 within which is arranged for operation a piston 61.

Leading from the tube 24, which latter leads from the main control valve 22 to the reverse ram, to the upper endof the cylinder 60, is a fluidpressure pipe 62 and by virtue of this last mentioned pipe fluid pressure passes from the conduit 24 to the upper end of cylinder 60, at the same time that fluid pressure passes from the main control valve to the reverse ram.

Arranged for sliding movement through rods. These expansive springs yieldingly resist the downward movement of the rods 63 that carry the brake shoe 64, and under nor mal conditions said springs hold the rodsv and the brake shoe at their upper limit/of movement. 3

While the shovel is in operation the main drum gear wheel 12operates continuously andfas pini'on29 meshes with the main gear wheel, shaft 18 .will' be constantly rotated,

and the speed j of rotation will be -relatively high due to the relative sizes of the main drivewheel and the gear wheel 29.; :f a

Inasmuch as the disks 31 are keyed to shaft 28 said disks will rotate-constantly but until clamping pressureis applied to said disks they will not. impart rotary motion to.

Y the cable-drum'34. Thus as the dipper is moved downwardly and outwardly while beingfilled the cable 18 will unwind from the ".ClI'lll'll 34 inasmuch as the latter is free to rotate upon the hubs of the disks 31.

, its fulcrum so fasto pull the flexible member 55through itssheath or housing, thereby ac- 1 v tuating bell'c'rank 51 so asito'move 'push'rod.

43 outwardly through bracket 41 and arm 40.

As a resultof this operation the lower end of lever 46 is moved toward the drum 34 and the lugs 49 engaging thrust bearing 33 moves theinner one of the friction disks 31 against --.the corresponding face of drum 34, and as the outer one of the: friction disks is held against movement by the nut 32 the winding drum will be engaged by theclutch .facings 351sothat said drum will be picked up and rotated with the constantly rotating friction disks 31. As drum 34 is thus rotated, cable exerting pull-upon the latch-'17 soa's torelease the dipper door and when such operation has been'. effected the operator releases pressure on the pedal 53, which actionrelieves the pressure applied tothe friction disks byrthelever 46-. thereby breaking the driving connection between said friction disks and the l a cable carrying drum 34 sothat the'latter ceases to rotate.

The tensionoif' spr1ng-45-1s such as to pro slack in cable 18, but the pressure of said spring is insufficient to bring about a rotation of the cable drum and cause the cable that winds thereonto to release the latch 17.

In other words the latch releasing operation is only accomplished by actuation of the pedal 53 and actuation of the parts-connected and controlled thereby.- v

The flexible member 55 and its sheath 56 between the bell crank 54 that is actuated by:

thepedal and'the'bell crank 52 that is connected to said flexible member and which iniparts movement directly to the push rod 43.

v When-the proper one of the control levers 21 ismanipulated so'as to actuate the main control valve 22 and permit fluid pressure to pass throughipipe to the reverse ram fluid pressure will at the same time pass through pipe62 into the upper end of cylinder 60, thereby moving piston 61 downwardly and in turn-the brake shoe 64' will be moved downwardlyto' engage the coils of cable that is wound upon drum 34, and such actionpr'es vents the cable on said drumfrom unwinding while the shovel is being reversed or moved rearwardl'y. I a

When the fluid pressure is cut off to cylinder the springs 65will act to instantly elevat-e the brake shoe 64.

Thus it will be seen that I have provided relatively simple, practical and inexpensive means for positively controlling the operation of the drum that carries thecable that actuates the dipper door latch and which means is strong and durable in structure and capable of being readily applied to all makes'of gasoline orgas air shovels without Specialmachine work or wlthoutrequlring special castmgs or extraneous parts.

The pedal that controls the'operation oftlie V V latch releasing means is conve 'ii'entl'y located nnmediately in front of and below the operatorsseat and as the'latch releasing meansls directly connected to the main drum gear wheel of the shovel by a relatively small gear or piniong'said latch releasing means is capa-' ble of being positively actuated at all times and due to the relative sizes of the main gear-wheel and the pinion the operation of'the latch releasing device is comparatively rapid. 18' will be wound upon saiddrum; thereby The nut 44 provides means whereby the tension of spring 45 may be accurately reg'u' lated and nut '50 provides means for-adjusting,

the. position of the lower end of lever 46relative tot-he push rod, and as a result of these two adqustments a very accurate regulation of the-normal tension betweenvth'e' friction :in the size, form antl 'construction of the various parts of my improved power dipper door latchrelease'may be made and substi= tutedfor' those herein'shown' and described without departing fromthe spirit of myinvention, the scope of which is set forth in the appended claims;

I claim as my invention device, a rotatably'mounted shaft, a winding door latch of theshovel with which thed 1: In a power dipper door latch? releasingvice is associated, means providing a slip drive connection between said drum and shaft, whereby said drum tends to rotate to wind the cable thereon, and maintain the same under atension insufficient to actuate the latch, an arcuate brake shoe arranged for operation adjacent to said drum, means for moving said brake shoe into frictional engagement with the cable on said drum, and pedally actuated means for providing a greater frictional connection between the drum and shaft whereby tension is applied to the cable suiiicient to release the door latch. 2. The combination with a power shovel :and the latch of the dipper door associated therewith, of a trip cable connected to said latch, drum on which said trip cable is wound, a constantly rotating shaft carrying said drum, means for imparting the rotation f the shaft to said drum to keep slack out of the cable, but not sufficiently to positively actuate the cable to trip the dipper, an arcuate brake shoe arranged for operation cent to said drum, means for moving said bralre shoe into frictionalengagement with the cable on said drum and pedally actuated means for imparting rotation of the shaft to the drum towind the cable thereonte and to trip the dipper door latch.

3. The combination withapower shovel,its main control valve and the latch of the dipper door that is associated with said shovel, of a constantly rotating shaft, a cable secured to and adapted to wind onto said shaft, which enable is connected to the dipper door latch, a cylinder, a piston arranged for operation therein, a brake shoe arranged between said piston and the coils of the cable carried by said drum, and a fluid pressure conduit leading from the main control valve to said cylinder.

4c. In apower shovel dipper door latch release, the combination of a drum, a cable secured to and adapted to wind onto said drum, which cable is connected to the dipper door latch, a cylinder positioned adjacent to the periphery of the drum, a piston arranged for operation within said cylinder, means for admitting fluid pressure to said cylinder, and a brake shoe adapted to be engaged by the piston and moved into engagement with the coils of the cable on said drum.

5. In a power shovel dipper door latch release, the combination of a drum, a cable secured to and adapted to wind onto said drum,

which cable is connected to the dipper door latch, a cylinder positioned adjacent to the periphery of the drum, a piston arranged for operation within said cylinder, means for admitting fluidpressure to said cylinder, a brake shoe adapted to be engaged by the piston and moved into engagement with the coils of the cable on said drum, and means associated with said brake shoe for withdrawing the same from engagement with the coils of the cable.

6. The combination with a power shovel, its dipper door latch, its main control valve and the pipe leadingfrom said valve to the reverse ram, of a drum, a cable secured to and adapted to wind onto said drum, which cable is connected to the dipper door latch, a constantly rotating shaft, pedally controlled means for imparting the rotation of said shaft to said drum, a cylinder disposed adjacent to said drum, a piston within said cylinder, a brake shoe adapted to be engaged by said piston and moved into engagement with the coils of cable on the drum, and a fluid pressure conduit leading from the pipe that leads from the main control valve to the reverse ram to said cylinder whereby the piston within said cylinder is actuated simultaneously with the actuation of the reverse ram.

7 In a power dipper door latch releasing device, a rotatably mounted shaft, a pair of friction disks carried by said shaft and adaptedto rotate therewith and to move toward and away from each other, a drum mounted for independent rotary movement between the said disks, a cable secured to and adapted to wind onto said drum, which cable is connected to the dipper door latch, means for moving one ofsaid friction disks toward the other to frictionally engage said drum, a pedal, flexible connections between said pedal and the friction disk actuating means, an arcuate brake. shoe arranged adjacentto said drum and means for moving said brake shoe into frictional engagement with the cable on said drum. 7 V

8. The combination with a power shovel and the latch of the dipper door associated therewith, of a trip cable connected't-o said latch, a drum on which said trip cable is wound, a constantly rotating shaft carrying said drum, means for imparting the rotation of the shaft to said drum to keep slack out of the cable, but not sufficiently to positively ac- 

